Laser safety system

Abstract

A laser safety system providing a system for checking the presence, focus and integrity of a laser beam focusing lens is disclosed. The laser safety system checks the focusing lens properties by capturing an image of a target by viewing the target through the focusing lens from along the laser beam path. An initial, known good, image is compared to an image captured immediately before enablement of the laser beam source to determine if the focusing lens is present, focused and is not damaged. The system may also utilize a mask projected onto the target as well as a low-power visible light laser directed along the path of the processing laser to determine the focusing lens properties. The system can also provide target recognition.

Description

RELATED APPLICATIONS [0001] The present invention claims priority from U.S. Provisional Patent Application Ser. No. 60 / 797,102 filed May 2, 2006, which is incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates generally to safety systems for lasers, and more particularly to a method and apparatus for testing laser beam focus and beam alignment prior to operating the laser system, and for taking a safety action if the system is not in proper working condition. [0004] 2. Brief Description of the Prior Art [0005] Many types of laser-based devices and systems, having a wide range of applications in fields such as manufacturing, research, communications and medicine have become increasingly well-known and commercially available. The lasers used in many of these devices and systems are often capable of producing energy output that is potentially harmful to both people and equipment. [0006] The potential dangers as...

AI Technical Summary

Benefits of technology

[0020] Another object of the present invention is to provide a method for indicating the safe operability of a laser beam focusing lens in which a low-power visible light laser beam is projected through a laser beam focusing lens and onto a target, wherein the figure projected by the low-power visible light laser beam onto the target area is observed and a processing laser beam is enabled when the characteristics of the projected figure meet predetermined specifications, and wherein the processing laser beam is disabled when the characteristics of the projected figure do not meet predetermined specifications, and in such a case a visual or audibly perceptible alarm is produced.

[0021] Another object of the present invention is to provide a method for indicating the safe operability of a laser beam focusing lens wherein a mask pattern is projected onto a laser beam target from a light source other than the processing laser, and wherein an initial image of the masked target is captured through the laser beam focusing lens when the focusing lens is in focus, in good condition and present, and wherein a second image of the masked target as seen through the laser beam focusing lens is captured before beginning a laser processing operation, and wherein the images are compared and the laser system enabled when the second image and the initial image match within a predetermined margin for error or disabled when the second image and the initial image do not match within a predetermined margin for error, and wherein if the laser system is disabled a visually or audibly perceivable alarm is produced.

[0022] An object of the present invention is to provide a laser positioning safety system including a beam steering device, a work surface, at least one signal source, and at least one signal sensor, wherein the signal sources and signal sensors are associated with the beam steering device and the work surface in a signal sensing orientation, and wherein a signal produced by the signal sources is detected by the signal sensors when the beam steering device is positioned within a safety zone for laser processing, and wherein the detection of the signal indicates that the beam steering device is oriented to allow safe operation of the laser system.

[0023] Another object of the present invention is to provide a laser positioning safety system including at least one camera, at least one visual target, at least one image of the visual targets, a beam ...

Problems solved by technology

The lasers used in many of these devices and systems are often capable of producing energy output that is potentially harmful to both people and equipment.

Further, some forms of laser radiation can damage an unprotected human eye even before it has time to react to the exposure.

This may lead to considerable physical damage to the eye, such as cutting or burning, and can also result in temporary or permanent vision impairment or blindness.

At other focal lengths however, the laser radiation may be harmful even at long distances from the source.

Another potential danger associated with lasers is that of chemical vapors, dust or melted liquids that may be formed in the area where the laser interacts with a work surface, such as in laser welding or scribing.

The harmful properties of these chemicals may adversely affect nearby persons if inhaled or otherwise transferred to the body.

Class II systems are considered a hazard for direct long-term ocular exposure.

Class III system emission levels are ocular hazards for direct exposure and may be hazardous to skin at longer exposure times. Class IV systems are the most hazardous and pose a danger to eyes and skin upon direct, as well as indirect exposure such as that resulting from scattered, diffused or reflected radiation.

However, for reasons such as costs and performance requirements, laser systems are often operated at more dangerous cl...

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